ACTG 359 - Activity of the Soft Gelatin Capsule of Saquinavir (SQVsgc) in Combination with Ritonavir or Nelfinavir and Combinations of Delavirdine, and/or Adefovir Dipivoxil in HIV Infected Subjects with Prior Indinavir Use and Viral Loads of >2,000 and <200,000 Copies HIV RNA/mL; This study will determine whether one or more of three or four drug combinations of saquinavir, nelfinavir, ritonavir, delavirdine and/or adefovir dipivoxil will reestablish control of viral replication in HIV-1 infected individuals who have failed therapy with indinavir-containing regimens. It is hypothesized that a control of viral replication can be reestablished in such individuals because of the non-overlapping resistance patterns of these drugs with each other and with indinavir. This investigator-initiated, NIH-sponsored 'A' trial is a randomized, partially blinded, multi-center study. All subjects will be randomized to one of the following treatment arms: ARM A: SQVsgc 400mg bid + ritonavir 400mg bid + delavirdine 600mg bid + adefovir dipivoxil placebo qd. ARM B: SQVsgc 400mg bid + ritonavir 400mg bid + delavirdine placebo bid + adefovir dipivoxil 120mg qd. ARM C: SQVsgc 400mg bid + ritonavir 400mg bid + delavirdine 600mg bid + adefovir dipivoxil 120mg qd. ARM D: SQVsgc 800mg tid + nelfinavir 750mg tid + delavirdine 600mg bid + adefovir dipivoxil placebo qd. ARM E: SQVsgc 800mg tid + nelfinavir 750mg tid + delavirdine placebo bid + adefovir dipivoxil 120mg qd. ARM F: SQVsgc 800mg tid + nelfinavir 750mg tid + delavirdine 600mg bid +adefovir dipivoxil 120mg qd. Subjects who have an average HIV RNA value that is either <5,000 copies or at least one log below their baseline value, may continue on treatment for an additional 24-weeks. Subjects with plasma HIV RNA > 5,000 copies/mL who are receiving study medications in the treatment extension may elect to continue study medications, or discontinue study medications and seek best available treatment.